feat: Allow escaping of context mentions

[KJ7LNW]

Context

Fixes #2931.

This PR implements the core functionality to allow escaping of context mentions with backslashes, enabling users to pass CLI-style arguments like @/foo literally without triggering file content expansion.

This PR is a focused implementation of the core functionality requested in issue #2931, separated from the UI changes that were proposed in PR #3088. The UI changes will be implemented in a separate PR+issue combination as requested by @hannesrudolph.

Implementation

1. Mention Parsing (src/shared/context-mentions.ts)

   • The mention parser now includes a negative lookbehind (?<!\\) in the regex to ignore escaped @ symbols.
   • Tests updated to confirm that \@foo is ignored and \\@foo is interpreted as @foo.

2. Subtask Unescaping (src/core/tools/newTaskTool.ts)

   • In newTaskTool, \\@ is converted to \@ before initializing the subtask.
   • This ensures each subtask layer peels off one escape level, preserving intended mentions.

3. Tests

   • Added tests to verify correct behavior with one or more levels of escaping (\@, \\@, \\\\@).
   • Confirms proper transformation and message integrity across nested tasks.

Get in Touch

Discord: KJ7LNW

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Important

Adds functionality to escape context mentions using backslashes, updating regex and task handling logic, with corresponding tests.

• Behavior:
  • Allows escaping of context mentions using backslashes in context-mentions.ts.
  • Updates mentionRegex to include negative lookbehind (?<!\\) to ignore escaped @ symbols.
  • In newTaskTool.ts, converts \\@ to \@ before initializing subtasks.
• Tests:
  • Added tests in newTaskTool.test.ts to verify unescaping behavior for \\@, \@, and @.
  • Updated context-mentions.test.ts to confirm regex changes handle escaped mentions correctly.
• Misc:
  • Fixes Need escape mechanism for '@' symbol to prevent unwanted file content expansion #2931 by implementing core functionality for escaping context mentions.

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[daniel-lxs]

Thank you @KJ7LNW, This looks good.

As I mentioned in the previous PR, this new functionality needs a good documentation, some examples of the behavior regarding subtasks since it is quite confusing even for the agents reading the code.

cc: @hannesrudolph